Looking for advice on a forge

[genesaika]

Ok, so I'm new to this, but have been looking into it and thinking about starting for a long time now. I've done a lot of welding and fabrication, I'm not certified or anything, but working in the field will teach you a lot. I've been looking on YouTube a lot and noticing that most of the forges there are dangerous at best... 

Anyways, my goals with this will come in stages. I'm planning to be working on knifes as a hobby and starting with just some stock removal and heat treating. After I find, or make, an anvil I want to move on to actually forging steel. Finally I want to be able to do some forge welding and try my hand at layered steel. Of course I'm not expecting this to be a quick journey so take these goals as long term, I would like to have a forge that can handle this though.

Now for my plan so far. I have seen many forges and jumped between fuel types and then forge shapes, but I've decided on running propane and building a square box forge. I got the forge shape from YouTube, Alec Steele has a build video of it, in the video they build it using hard firebrick for the floor, soft for the sides and ceramic fiber board for the roof. This doesn't seem to be very efficient to me honestly, but I want to use the shape because it seems easier for me to make. It will be a metal box with 1/4in thick walls, in the video it's size is about 9in x 9in x 9in based on the firebricks.

I'm hoping to get some advice on how to properly refactor this forge for my needs, or wants. Would the working area be enough for me? Based on the firebricks sizes it has a 4in x 4in x 9in interior.

Finally I'm planning on using a Mikey burner to heat this thing up. I'm guessing that all I would need is a 3/4 burner, but I'm hoping to hear from the more experienced members here on that. I would also like to know where I could source a reliable prebuilt one. I've seen a few burners on eBay for around $50, but I don't know what type they are or if they can be trusted.

Well thank you all for any information you provide.

 

[Binesman]

So youre shell will be a 9" metal cube.  

My recomendation to you is 2 layers of 1" 8# ceramic blanket for the sides and top with a 1 layer of 1" on the bottom.  (ridgidize your blanket 1 layer at a time)Then place a layer of 1 1/2" hard firebrick for the floor.  Then trowell on a 3000f refractory like kastolite 30 over the entire inside and let it set.  Then coat it all with matrokite90ac.  That forge will do anything you want it to and be sturdy.

 

As for vuying a burner theres a lot of options for a decent price mathewson forge isnt bad.

[genesaika]

 

So youre shell will be a 9" metal cube.  

My recomendation to you is 2 layers of 1" 8# ceramic blanket for the sides and top with a 1 layer of 1" on the bottom.  (ridgidize your blanket 1 layer at a time)Then place a layer of 1 1/2" hard firebrick for the floor.  Then trowell on a 3000f refractory like kastolite 30 over the entire inside and let it set.  Then coat it all with matrokite90ac.  That forge will do anything you want it to and be sturdy.

 

As for vuying a burner theres a lot of options for a decent price mathewson forge isnt bad.

That's about what I expected would be the best option. Any idea how much kastolite 30 and matrikote 90ac I would need? Would making the outer layer of ceramic blanket in multiple pieces be a bad idea? 

I think the Mathewson burner was one of the ones I had seen on eBay. $85 for the burner, regulator, and hose isn't bad.

[ThomasPowers]

Why so heavy a shell?    Also it seems like you plan to change your usage of it over time.  Forges are a consumable and gas forges tend to be  specific for the use.

So if you plan to put in a gravel driveway six to eight years down the road---would you buy a dumptruck for your daily driver now so you can use it then?   Build the forge you need now and just make another as your needs change is my advice.

 

[Mikey98118]

For a forge with a 9" x 9" x 9" interior, a 1/2"  size Mikey burner would do, but the 3/4" can be turned down low enough to serve if you just want the larger burner on hand for other projects.

The main point of brick pile forges is their adaptability. There is nothing adaptable about a solid steel shape of any kind; it can be desirable for other reasons, none of which apply to brick forges. Consider an angle iron exterior frame instead.

The logical material for the top of a brick forge is...brick. Transforming separate bricks into a monolithic surface is what high-temperature mortar is for; it has been doing so in pottery kiln lids for a long time.

So, what kind of brick do you want in for your forge? Morgan "K" series bricks from Thermal Ceramics will give you the most bang for your bucks. In accordance with the KISS formula, use a thin layer of Kast-O-lite 30 on the hot-face side, or mix up some zirconia silicate with 5% bentonite. for the coating. Use K26 brick for best efficiency; shipping rates are relatively low on this product because it is lightweight.

For the forge floor, I would recommend a 1/2" thick layer of Kast-O-lite 30. A high alumina kiln shelf would be more convenient; but only if you trust the supplier not to sell you something second-rate as the real thing.

The K26 bricks can be purchased on eBay.

[WayneCoeArtistBlacksmith]

I suggest that you read the Build a Gas Forge at the Forge Supplies page of my web-site.  You can get the URL and contact information by going to my Profiles page.

If you want to contact me I prefer e-mail.

Let me know if I can help you.

Wayne

[genesaika]

Thomas, the shell is so heavy because that's what I have ready access too for free. If a lighter shell would be better I might be able to find enough 1/8 steel. I'm not too concerned about the weight because I plan on making a cart to keep it on. As to why I want it so advanced... Well I'd rather have the tool I will need when im ready to advance instead of haven't to stop to build a new one.

Mike, I feel like there was some confusion. The video I watched did use a brick pile forge, but I feel it's too inefficient and want something more permanent that I can adjust the temperature on to handle multiple tasks. Would the 1/2 burner be effective for welding? Also where could I buy one in that size?

Wayne, I haven't read your information yet, but will be sure to tonight. If I have any questions I will ask.

[ThomasPowers]

OK free is a valid reason---I have one propane forge made from light grain auger tubing and one made from Oxy Tank.  The heavy one is a pain to move but I mounted a sliding work rest to it and it will handle most of my stuff with no problem.

You do realize that you may be rebuilding it anyway, perhaps a couple of times before you are reading for forge welding billets in it right?    However your forge your choice.

As to size and welding---many factors in the heat balance, (rate of heat entering vs rate of heat leaving).  More insulation and/or bigger/better burner and/or lower interior size  all factor in. (as well as openings too).

[MonkeyForge]

You state:

"Anyways, my goals with this will come in stages. I'm planning to be working on knifes as a hobby and starting with just some stock removal and heat treating. After I find, or make, an anvil I want to move on to actually forging steel."

This is a small goal, and also a good goal. I think you will be better of making a small forge. With a good burner your small forge will get metal hot enough to be plastic or hot enough to heat treat simple steels (we have threads on heat treating). I think most principles will scale up from a small forge/burner to bigger ones. If you cannot get any of the required materials in small quantities a large fore will be appealing but you can probably order a large quantity of materials and build a small forge. you should have enough left to build a bigger one when you need it.

For specifics forges 101 and burners 101 in the stickies are a good read. And heed the advice of the guys posting in your thread prior to me. They are a wealth of information.

[genesaika]

Yes Im aware that I will likely rebuild it at some point. I will also likely build more, but I want to build this one to keep my shop small due to a limited space. I will most likely have everything on carts so I can roll them inside when not in use and use a pop up tent( with some sort of walls) as my work shop.

Would I be better off making it smaller? I chose the size simply because the bricks fit in it nearly. I would like to keep the length at 9in but I think I could get away with going as low as 6in for the height and width. That should still give me enough space to have a 1-2 inch layer of insulation on all sides. Would a 1 inch layer of insulation be enough?

[Mikey98118]

 The only commercial source for by burner design is Chile Forge; they only build it in 1" size. However, its for runner can be purchased in 3/8", 2/8",  1/2", 3/4",   and 1" sizes from Hybridburner.com. There are other commercial burners, such as Devil Forge; who sell well their burners in more than one size.I have seen proper flames exiting at least one of their burners, but have no idea if all of their burners produce such flames.

Let's try that again:

The only commercial source for my burner design is Chile Forge; they only build it in 1" size. However, its forerunner can be purchased in 3/8",  1/2", 3/4",   and 1" sizes from Hybridburner.com. There are other commercial burner sources, such as Devil Forge; who sell their burners in more than one size. I have seen proper flames exiting at least one of their burners, but have no idea if all of their burners produce such flames. There are good burners becoming available in a steady stream, but if you can't see them running in a video, you must take to take your chances; those are about one in six. What; you thought all those guys who choose to build their own burners are trying to save money?

[genesaika]

Well I wasn't really thinking it was just to save money. I'm my particular case though building one involves buying more tools next month and pushing back my timeline even farther. 

Maybe I can source the parts that I would need to drill?

[Binesman]

Gene you can have a burner yp and running with nothing more then a dremel and a drill.  Go to your local ace hardware get a 10 inch long 3/4" black pipe nipple.  A 1" to 3/4" black pipe reducer.  A 3/8" flare by 1/4" pip brass elbow and a 1/4" brass cap.  For the dremmel you will need 80 grain sand paper rolls and a #60 drill bit.  If you dont have a tap set youll also need a hose clamp

 

On the 1" side of the reducer use the dremel to sand out all the threads and the slight "bump" to the step up so its smooth.  Screw the 3/4" end on to the nipple.  Then use the dremmel to drill a number 60 hole in the center of the 1/4" cap and connect it to the elbow.  Drill 3 sets of 4 (total of 12)  3/8" holes starting about 3 inches from the top of the nipple (the top is the side with out the reducer) stick the elbow in the top with the 1\4" cap pointing straight down the middle.  Either drill and tap holes or use the hose clamp to hold it in place.  Hook your propane up to the 3/8" flare and youre good to go.

[WayneCoeArtistBlacksmith]

Gene, you should be able to get 20# Propane tanks for free because the ones with the old valves can't be refilled.  You should be able to get a truck load of Freon bottles for free at your local HVAC company or auto repair shops that do AC work.

[Frosty]

Welcome aboard Gene, glad to have you. Beware advice from guys who have exactly ONE burner to their name and really complicated builds. Look at the Illustrated T burner instructions here for probably the easiest to build reasonably efficient burner going. I'm SURE you know someone who has a drill press you can use for half an hour or so. No?

You're making a common mistake we all make. You want to make a piece of equipment that will last many years that you don't know how to use. Please forget Youtube, all you need to be a Youtube expert is a camera and service provider. Too many how to videos are dangerously BAD method and products Anyway, you WILL be building more forges, believe me everybody who's been making the things has a couple gathering dust under a bench or shelf. About 4 hrs. into it's working life I decided to replace my latest build. Honest, it's brand new and obsolete at the same time. It happens to us all, Honest.

The shell I put on gas forges is 16 ga. steel with a 1/8" x 1" angle iron frame. You don't need a welder, a drill, bits, pop rivet puller or sheet metal screws, is the joinery MEL (Minimum Equipment List) to build the shell. You can do all your cutting with a saber saw or hack saw. You want more coarse TPI for thicker steel. like the angle than you do for the sheet. MORE teeth is NOT better!!

You aren't going to be working heavy projects, 2-3 lbs. is a big billet for blades a person can use in real life. 

I don't have any experience with the K series bricks made by Morgan, Mike references but I take him at his word, he's not a BS guy. Makes mistakes of course but if he says something's good, it is. 

1/2" of KastO-L-ite30 li has stood up to some pretty serious abuse from first timers and a couple guys with no idea what take it easy means. The floor on that forge is two layers of 1" 8lb. Kaowool. (Yes you can use pieces to make up walls, floors, etc. the roof is more structurally secure as single pieces) The insulating ceramic refractory blanket is rigidized and covered with 1/2" of KastO-L-ite 30.

The entire interior of the forge is built the same way, I can sit a plastic coffee cup on top of it in use and it doesn't melt in contact with the shell. Exhaust fumes made it saggy though when a breeze blew that direction, it was an experiment after a couple hours in operation. 

If you wish to build your forge and or burner(s) pick one set of plans and follow them. Do NOT mix designs! This is a B-A-D idea unless you have more experience than most guys will ever need. Mike and I don't combine our burner designs though there are a couple features worth experimenting on. I don't know how long Mike has been building burners but he's published a pretty darned complete book on the subject. I've been making the T for a little more than 30 years or so. Two different designs, Mike developed max efficiency in a home build where I developed one that's efficient and easy to build with minimum tools and shop skills. I designed an old pickup truck burner and Mikey designs Ferraris.

If you have problems or questions about the burner build, ask the author first. Asking on a public forum with more than 45,000 members will get a LOT of help from people with little or no experience. I'm not dissing anybody, everybody wants to help unfortunately we often jump the gun and offer help that really isn't. The other side of that coin is there are guys who's ideas are unpolluted by knowledge out there making burners that work beautifully. Mike and I both look at the things and start ticking off all the things wrong with them till we look at the flame and we shut up. Recently I've stopped commenting on these burners except to offer advice tuning them, I've been completely wrong too many times to think I'm "right."

Wayne offers small quantities of most everything you need to build a forge at reasonable prices. We buy 50lb. sacks and split it among club members. There are also good and tested plans for forges, burners and such on the site. He's also a pretty helpful guy.

Frosty The Lucky.

[Mikey98118]

Frosty,

Ditto for me; last year I called something a "junk" burner, even though it was making a perfect flame. I was angry that something that crude should make such a flame. Afterward, my conscience beat me up over it. Since then, I only judge a burner by its flame, and that is fortunate because more such flames are exiting burner designs that I don't approve of. "If it's dumb, but it works, it ain't dumb"